Opening Width • Bearing • Concrete Volume • Rebar Takeoff
Use this Concrete Lintel Calculator to estimate total lintel length from an opening and user-specified bearing, calculate concrete volume and ready-mix quantity, estimate lintel self-weight, and prepare a reinforcement takeoff from an already approved lintel design. It is a quantity-planning tool—not a structural span, load-capacity or reinforcement-design calculator.
Calculate approved lintel geometry, concrete quantity, self-weight or reinforcement takeoff.
Add user-entered bearing lengths to the clear wall opening to calculate total lintel length.
Quantity geometry only. The calculator does not determine whether the entered bearing is structurally adequate.
Estimate concrete volume from approved lintel length, width and depth, then convert to ready-mix or bagged concrete.
Bag yields are approximate planning values. Verify the actual manufacturer yield and ready-mix supplier minimums.
Estimate member self-weight from lintel geometry and user-entered concrete density.
Do not use this result to select lifting equipment without an approved lifting plan and verified actual member weight.
Convert approved longitudinal-bar and stirrup details into approximate steel quantity and weight.
Enter approved extension, development or anchorage allowance if applicable.
Use approved bar-bending schedule or calculated cutting length.
Reinforcement takeoff only. Never use this calculator to design structural reinforcement.
A concrete lintel is a beam-like structural element placed over an opening in a wall, such as a door, window, service opening or large passage. Its job is to bridge the opening and transfer supported loads toward the wall or structural support on each side. The International Code Council defines a lintel simply as a beam placed over an opening in a wall.
Concrete lintels may be cast in place, precast, integral with a reinforced concrete wall, or formed within insulated concrete form and masonry systems. Their dimensions and reinforcement are not chosen only from the opening width. Supported wall weight, floor or roof loads, wind or seismic conditions, concrete strength, reinforcement, bearing, wall type and local code requirements can all affect the structural design.
For that reason, this Concrete Lintel Calculator focuses on quantity takeoff after the lintel has been designed. It can help convert an approved opening/bearing detail into total lintel length, calculate concrete volume, estimate self-weight, and total reinforcement quantities entered from the approved schedule.
Use the lintel schedule, structural drawings, engineered detail or approved manufacturer table.
Calculate total lintel length from clear opening plus approved support on both sides.
Enter approved width and depth to calculate ft³, yd³, m³ and bag equivalents.
Use project-specific density when member self-weight is useful for handling or planning.
Enter approved bar quantities and spacing to estimate total steel length and weight.
Bearing values are user inputs and must come from the approved structural design or applicable prescriptive detail.
Width and depth entered in inches are divided by 12 before the volume calculation.
The calculator defaults to a planning density input that can be edited for the actual concrete mix.
Approved extension or development length can be entered separately at both ends.
This converts an approved spacing into a preliminary count. Final placement must follow the actual reinforcement drawing or bar schedule.
The clear opening is only the unsupported portion under the lintel. The physical lintel normally extends beyond the opening so it can bear on supporting wall material or other structural support. The total member length is therefore greater than the clear opening width.
The calculator does not supply a default bearing because structural support requirements vary. Concrete-wall systems, masonry walls, precast lintels, cast-in-place beams and proprietary products can have different detailing. The International Code Council's published lintel provisions show that lintel requirements can depend on wall type, opening width and supported loading conditions; reinforcement and lintel tables are system-specific rather than universal.
Always measure the clear structural opening rather than a finish dimension that includes trim or nonstructural material. Then add the actual approved left and right bearing from the structural detail. If bearings differ, enter them separately rather than assuming symmetry.
Lintel width is often coordinated with wall thickness, while lintel depth is selected to satisfy structural and detailing requirements. Those dimensions affect concrete volume dramatically. Doubling lintel depth approximately doubles the volume and self-weight if all other dimensions remain unchanged.
Do not use a simple rule such as “opening width divided by a fixed number” to choose lintel depth for a structural opening. Load path, support conditions, reinforcement ratio, shear, deflection, cracking, concrete strength and construction configuration all matter.
Once the approved section is known, the volume calculation is straightforward. Convert width and depth from inches to feet and multiply by total lintel length. For several identical openings, multiply by the lintel count.
Suppose an approved detail shows a lintel with a total length of 7 ft, a width of 8 in and a depth of 12 in. Convert 8 in to 0.667 ft and 12 in to 1.0 ft. The concrete volume is approximately:
If three identical lintels are required, the exact combined volume is about 0.519 yd³ before any ordering allowance. Small cast-in-place lintels may be practical to produce from bagged concrete in some situations, while multiple or larger lintels may be supplied as part of a ready-mix pour. Always follow the specified concrete strength and mix requirements.
For other project elements, use the main Concrete Calculator or Concrete Pour Calculator to combine lintel volume with walls, columns, slabs or other concrete placements.
Measure the opening, use approved bearing and section dimensions, then calculate concrete and reinforcement quantities from the design documents.
Concrete lintels can be heavy even when their volume appears small. Self-weight matters for formwork, shoring, precast handling, lifting and structural load calculations. The weight calculator multiplies concrete volume by the density entered by the user.
A planning value may be useful for early takeoff, but actual density varies. Lightweight concrete, normal-weight concrete and specialty mixes can differ significantly. Reinforcing steel, embedded plates and other hardware also add weight.
If a lintel is precast and lifted into position, do not select a crane, hoist, lifting insert or rigging system from this calculator alone. Use the actual member drawing, verified weight, approved lifting points and a competent lifting plan.
Reinforced concrete lintels commonly contain longitudinal bars to resist flexure and may contain stirrups or other transverse reinforcement for shear and confinement. The structural arrangement depends on the lintel system and loading.
The calculator's rebar panel intentionally asks you to enter the bar count, size, extension length and stirrup spacing. These values must come from the approved structural design. The tool then converts those inputs into approximate cutting length and steel weight.
For larger reinforcement schedules, use the Concrete Rebar Calculator and Concrete Rebar Length Calculator to organize quantity takeoff. Always preserve the designer's actual hooks, development lengths, laps, cover and placement zones.
Code and standard provisions demonstrate why a one-size-fits-all lintel rule is unsafe. Published ICC provisions for certain concrete-wall systems use different lintel tables according to wall configuration and the loads supported above the opening. They also include specific reinforcement and stirrup requirements in defined conditions.
Those provisions are not a universal design table for every concrete lintel. A cast-in-place reinforced concrete lintel in a conventional structural wall may instead be designed as a reinforced concrete beam under applicable structural design requirements. Proprietary precast lintels may use manufacturer load/span tables.
For reinforced-concrete technical requirements, consult the current project-adopted standards and the American Concrete Institute. For building-code provisions and applicable editions, consult the International Code Council and the authority having jurisdiction.
A cast-in-place lintel needs formwork that maintains the required width, depth, alignment and elevation while supporting fresh concrete and construction loads. Openings often make soffit support more complex than an ordinary wall pour.
Before concrete placement, check that the lintel form is properly supported, reinforcement is fixed in its approved location, concrete cover is maintained, embedded items are installed, and the opening dimensions still match the drawings.
Form deflection or leakage can change lintel dimensions and concrete volume. Even a small increase in depth over a long lintel can add material. For material planning, calculate from the actual finished form dimensions immediately before the pour where practical.
Concrete should be placed so reinforcement remains in position and the section is adequately consolidated. Dense reinforcement or narrow lintel sections can make placement difficult. The concrete mix, aggregate size, slump or flow characteristics and consolidation method should be compatible with the approved specification and member geometry.
Avoid using water additions or improvised changes simply to make concrete easier to place. Follow supplier, specification and project requirements. Where pumping is used, the Concrete Pumping Calculator can help with volume and placement planning, but pumping pressure and safe line operation must be handled by qualified personnel.
Concrete gains strength over time, so a newly placed lintel should not be treated as fully capable simply because the surface has hardened. Curing conditions, concrete mixture, temperature and actual strength development matter.
Form and shore removal should follow the approved construction requirements and responsible professional guidance. Premature removal can subject the lintel to load before sufficient strength has developed.
Do not use a generic “number of days” from an online calculator as a substitute for project requirements. Where strength is critical, the construction documents or testing requirements should govern.
| Input | Why It Matters | Calculator Use | Who Should Define It? |
|---|---|---|---|
| Clear opening | Unsupported span below lintel | Total member length | Field measurement / drawings |
| Bearing | Support beyond the opening | Total member length | Approved structural detail |
| Lintel width | Section geometry | Concrete volume / weight | Approved structural detail |
| Lintel depth | Section geometry and structural behavior | Concrete volume / weight | Approved structural detail |
| Concrete density | Converts volume to self-weight | Weight estimate | Mix / project data |
| Bar count & size | Structural reinforcement | Steel takeoff only | Approved structural design |
| Stirrup spacing | Shear reinforcement layout | Takeoff count only | Approved structural design |
The lintel normally extends beyond the clear opening. Use the approved bearing on both sides.
Bearing is a structural design parameter, not simply a quantity preference. Enter the approved value.
Depth depends on structural demand and design. Use the scheduled dimension from project documents.
If a project has several identical openings, multiply concrete and reinforcement quantities by the actual count.
Longitudinal bars may extend beyond the simple lintel length to satisfy anchorage or development requirements. Use the approved detailing.
Some structural designs use different stirrup spacing in different regions. A single-spacing takeoff is only suitable when the approved detail actually uses one uniform spacing.
A lintel may support wall, floor, roof or other loads in addition to its own weight.
A correct volume or rebar quantity does not prove that a lintel is safe or code-compliant.
Use these related tools when lintel construction is part of a larger wall, reinforcement or concrete-placement project.
This calculator is intended for quantity takeoff only. It does not calculate structural bending capacity, shear capacity, deflection, crack width, bearing stress, anchorage, development length, splice length, reinforcement ratio, minimum reinforcement, fire resistance or serviceability.
It also does not determine the loads carried by the lintel. Supported masonry or concrete, floor and roof reactions, wind, seismic effects, point loads and construction loads may all matter.
Use the calculator only after the lintel geometry and reinforcement have been established through approved drawings, applicable prescriptive provisions, a manufacturer system, or qualified structural design. When in doubt, have the lintel reviewed by a structural professional before construction.
Common questions about lintel length, bearing, concrete volume, self-weight, reinforcement and structural limitations.